Move over, Mata Hari: the Ologies take a new direction with this spectacular addition to the series. Maintaining the beloved interactive format, the latest entry poses as a collection of items assembled in 1958 and stored in national archives, now declassified under the “fifty-year rule.” Agent K, a British spy, is tracking down the evil international Operation Codex, using his mission to ground a training manual for spies. Readers can match wits with Agent K as they pick up clues; absorb lessons in reading body language (too much eye contact might mean that someone is trying too hard to seem sincere), creating instant disguises or following someone; learn about famous spies; and more. Enticing extras include a red-tinted magnifying glass, a “secret compartment” concealed in the spine and a code-maker/-breaker. Who could resist? Ages 8–up. (Oct.)